Answer this question truthfully
### Question: What causes Somnolence?
### Response: Having to work long hours or different shifts (nights, weekends) Medications (tranquilizers, sleeping pills, antihistamines) Medical conditions (such as hypothyroidism, hypercalcemia, and hyponatremia / hypernatremia) Not sleeping for long enough Sleep disorders (such as sleep apnea syndrome and narcolepsy)